Evaluation of Plant Materials for Use in Reclamation of Disturbed Rangelands in Semi-Arid Areas of Northern Utah

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1 This file was created by scanning the printed publication. Errors identified by the software have been corrected; however, some errors may remain. Evaluation of Plant Materials for Use in Reclamation of Disturbed Rangelands in Semi-Arid Areas of Northern Utah Melissa V. Britton Val Jo Anderson R. D. Horrocks Howard Horton Abstract-Reclamation of degraded and disturbed rangelands in the arid west continues to be both desirable and difficult. At their best, reclamation practices and efforts often fail in their objectives due to harsh environmental conditions that tend to be difficult to predict. Development of species adapted to these harsh conditions improve reclamation success rates. The objective of this study was to test and select species that are adapted to two range site types in northern Utah. Between 20 and 24 species were used in replicated adaptability trials at two sites, sagebrush (Artemisia spp.)/grass and greasewood (Sarcobatus uermiculatus), located immediately southwest of Utah Lake in Northern Utah. Several species of both native and introduced grasses were evaluated as adapted to these sites, respectively. Alkar tall wheatgrass (Elymus elongatus) preformed well at the greasewood site, while crested wheatgrass (Agropyron crisfatum) varieties established well at the sagebrush/ grass site. A larger group of species performed well at the greasewood site than at the sagebrush/grass site. Reclamation and revegetation of arid and semiarid rangelands are difficult processes complicated by severe environmental conditions. Natural recruitment in areas of low precipitation is limited to wetter years (Roundy and Call 1988; Allen 1995). Developme'nt of improved plant varieties which are better adapted to dry areas can increase success of rangeland revegetation (Asay and others 1985; Munda and Smith 1995). Two vegetation types found in arid and semiarid areas of the Great Basin are sagebrush (Artemisia spp.)/grass and greasewood (Sarcobatus uermiculatus). types have a long history of reclamation (Young and others 1979). Seeding strictly with native species met with little success, and use of introduced species became necessary (Young and others 1979). Crested wheatgrass (Agropyron cristatum) was one of the first introduced species successfully tested and used in adaptability trials. Kellar (1979), in a review of species selection and seeding methods for sagebrush/grass sites, stated that crested wheatgrass has been the most important grass in revegetating these sites. Other important sagebrush/grass species included intermediate and pubescent wheatgrasses (Agropyron intermedium), Siberian wheatgrass (Agropyron cristatum), Russian wildrye (Elymus junceus), and dryland alfalfa (Medicago sativa) (Kellar 1979). Seedling establishment has proven difficult on greasewood sites, because of large amounts of salts in the soil (Forsburg 1953; Rollins and others 1968; Malcolm 1969; Sandoval and Gould 1978; Roundy and others 1983; USDA 1984; Roundy 1985). High concentration of salts can be toxic to plants, causing nutritional imbalances (Rollins and others 1968; Maas 1986), and reduced matric and osmotic potential of the soil (Sandoval and Gould 1978; Roundy 1985). In some greasewood sites the soils are sodic rather than saline (high salts but no excess of sodium). Sodic soils have a sodium adsorption ratio (SAR) greater than 13 and usually have a basic ph (Sandoval and Gould 1978; Jurinak 1981). Excessive sodium creates dispersed clay colloids in the soil which reduces infiltration of water into the soil (Rollins and others 1968; Sandoval and Gould 1978). Tall wheatgrass and basin wildrye (Elymus cinereus) varieties are among the few species which have proven to be successful on greasewood sites (Forsburg 1953; Fleck 1967; Rollins and others 1968; Malcolm 1969; McPhie 1973; Sandoval and Gould 1978; Roundy and others 1983; Roundy 1985). A sagebrush/grass site and a greasewood site in northern Utah were selected to test the adaptability of 20 and 24 plant species, respectively. The objectives of this study were to 1) evaluate establishment of selected species on the respective sites and 2) evaluate the longevity of green tissue for the same species. Study Site In: Monsen, Stephen B.; Stevens, Richard, comps Proceedings: ecology and management of pinyon-juniper communities within the Interior West; 1997 September 15-18; Provo, UT. Proc. RMRS-P-9. Ogden, UT: U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station. Melissa V. Britton is a Graduate Student at Brigham Young University. Val Jo Anderson is a Professor of range ecology at Brigham Young University, Provo, UT R. D. Horrocks is a Professor of agronomy at Brigham Young University, Provo, UT Howard Horton is a scientist with the USDA ARS in Logan, UT ' The study area was located in northern Utah immediately southwest of Utah Lake. This area receives an average of 250 to 300 mm of precipitation per year with the majority coming as snow or winter rain. The mean annual air temperature varies between 7.2 and 11.1 DC, and the frost free period is between 100 and 140 days. Soil types in the general area range from silt clay loams to sandy loams with a slope between 0 and 5 percent. 339

2 Table 1-Soil analysis for and sites. Soil test N itrate-n itrogen ppm N Phosphorus ppm P Potassium ppm K Salinity-ECe mmhos/cm Calcium ppm Ca Magnesium ppm Mg Sodium ppm Na Sodium Adsorption Ratio (SAR) , Two range sites were used to evaluate the adaptability of several species. The first site (sagebrush/grass), a semidesert gravelly loam range site (USDA 1993), was located 1 km north of Elberta, Utah and 2 km west of state highway 68. This was an upland site with current vegetation dominated by annual weedy species and interspersed shrubs and juniper trees. Analysis of these soils indicated a soil ph of 8.20, low levels of nitrogen and phosphorus, and high potassium levels (table 1). There were no problems with salinity or sodium on the site. Soil classification was Linoyer series, coarse-silty, mixed (calcareous), mesic Xeric Torrifluvents (USDA 1984). The second site (greasewood), an alkali flat range site (USDA 1993), was located 7 km north of Elberta, Utah and 2 km east of state highway 68. This site was dominated by greasewood with a sparse understory of other annual forbs and grasses. A soil analysis indicated a ph of 8.40 and low levels of nitrogen, but high levels of phosphorus and potassium (table 1). There were no problems with salinity, but a medium sodium hazard existed, with the site having a SAR of (Richards 1954). Soil classification was Manassa series, fine-silty, mixed (calcareous), mesic Xeric Torriorthents (USDA 1984). Materials and Methods At each range site the area was disked to remove the existing vegetation. The species to be tested were then seeded into a randomized four replicate complete block experimental design with 24 and 20 species in the sagebrush/grass and greasewood sites, respectively (table 2). Within each block, each species was planted in 10-row sections which were 3 m wide by 9 m long. Plots were seeded Table 2-Plant Materials used at study sites. Common name Oahe Intermediate Wheatgrass Luna Pubescent Wheatgrass Nordan Crested Wheatgrass P27 Siberian Wheatgrass Vavilov Siberian Wheatgrass Ephraim Crested Wheatgrass Hycrest I Crested Wheatgrass Hycrest II Crested Wheatgrass Douglas Crested Wheatgrass Broadleaf Crested Wheatgrass Critana Thickspike Wheatgrass Secar Snake river Wheatgrass Bannock Thickspike Wheatgrass Goldar Bluebunch Wheatgrass NewHy Hybrid Wheatgrass RSH Quackgrass Cross Alkar Tall Wheatgrass SL Hybrid Wheatgrass Magnar Great Basin Wildrye Trailhead Basin Wildrye Bozoisky Russian Wild rye Syn A Russian Wild rye Shoshone Beardless Wild rye Altai Wildrye Regar Meadow Bromegrass Paloma Indian Ricegrass Spreador II Alfalfa Alfagraze Alfalfa Remont Sainfoin Scientific name Agropyron intermedium Agropyron intermedium Agropyron fragile Agropyron fragile X desertorum X desertorum Elymus spicatus Elymus hoffmanni Elymus hoffmanni Elymus elongatus Pseudoroegneria spicata X Elymus cinereus Elymus cinereus Elymus junceus Psathyrostachys juncea Elymus trticoides Leymus angustus Bromus riparius Stipa hymenoides Medicago sativa Medicago sativa Onobrychis viciifolia Site planted 340

3 with a John Deere flex planter at seeding rates of approximately 11 kg per hectare. The sagebrush/grass site was seeded in the fall of 1992, and the greasewood site was seeded in the fall of In June of 1995, each plant species was rated for row uniformity and density on a scale from 1 to 10; 10 being the highest rating. Uniformity was an evaluation of plant spacing along the length of the row. Density was an evaluation of the relative number of plants per unit area. A stand performance index (SPI) was then calculated by multiplying the uniformity and density ratings. The longevity of green foliage was also evaluated for each species. The greenness of foliage was evaluated at 1 to 4 week intervals through the growing season, beginning May 19 and ending August 10. A rating of 70 percent indicated that 70 percent of the foliage was green and 30 percent was dry. Standard analysis of variance methods were used to compare species, and a protected LSD mean separation technique was used to distinguish performance between species (Ott 1988). A total of 29 plant species were seeded between the two sites, with some species being seeded at both sites (table 2). Results A wide range of density and uniformity ratings was found among plant species. The two ratings were tightly correlated for most species. The product of the density and uniformity ratings for each species was calculated, and used as a Stand Performance Index (SPI). Analysis of variance showed significant differences for stand performance among species (p :::; 0.01). Interaction between site and species was also significant (p :::; 0.01). Plant species were ranked in order from highest to lowest according to the Index for each site (tables 3 and 4). Siberian and crested wheatgrasses outperformed other species at the sagebrush/grass site. The top five varieties were P-27 Siberian, Ephraim, Hycrest I, Hycrest II, and Vavilov. These varieties scored significantly higher SPIs than the rest of the species. On the greasewood site, Alkar tall wheatgrass performed the best with a SPI almost 8 points higher than the other species, but it was not significantly higher than the other top 12 species (table 4). Remont sainfoin (Onobrychis uiciifolia) was ranked the lowest at both sites, being in the statistically lowest group along with five other species at the sagebrush/grass site (table 3), and being significantly lower than all other species at the greasewood site. Significant interaction between site and species occurred because plants such as NewHy and RSH quackgrass cross were in the statistically highest ranked group at the greasewood site, while being in the statistically lowest ranked group at the sagebrush/grass site. Overall, a larger group of plant species performed better at the greasewood site than at the sagebrush/grass site. Sixty-five percent of the species seeded at the greasewood site were in the statistically highest ranked group, with only one species beingin the statistically lowest ranked group. At the sagebrush/grass site only 21 percent of the species were in the statistically highest ranked group, while 25 percent were in the statistically lowest ranked group. Plant species at the two sites began to show statistical differences (p < 0.05) in percent greenness by the middle of July. By the last collection date, August 10, the differences Table 3-Species establishment at the site. Stand Rank Species Density Uniformity performance index 1 P27 Siberian Wheatgrass a 2 Ephraim Crested Wheatgrass a 3 Hycrest I Crested Wheatgrass ab 4 Hycrest II Crested Wheatgrass ab 5 Vavilov Siberian Wheatgrass abc 6 Syn A Russain Wildrye bcd 7 Broadleaf Crested Wheatgrass cde 8 Bozoisky Russian Wildrye def 9 Luna Pubescent Wheatgrass efg 10 Bannock Thickspike efgh 11 Nordan fghi 12 Paloma Indian Ricegrass fghij 13 Critana Thickspike Wheatgrass fghij 14 Trailhead Basin Wild rye hij 15 SL Hybrid Wheatgrass ij 16 Magnar Basin Wildrye j 17 Oahe Intermediate Wheatgrass j 18 Spreador II Alfalfa jk 19 Secar Snake river Wheatgrass kl 20 RSH Quackgrass Cross kl 21 NewHy kl 22 Goldar Bluebunch Wheatgrass Regar Meadow Bromegrass Remont Sainfoin

4 Table 4-Species Establishment at the site. Stand Rank Species Density Uniformity performance index 1 Alkar Tall Wheatgrass a 2 Vavilov Siberian Wheatgrass ab 3 Bozoisky Russian Wildrye ab 4 Nordan Crested Wheatgrass ab 5 P27 Siberian Wheatgrass ab 6 Hycrest I Crested Wheatgrass ab 7 Syn A Russain Wild rye abc 8 NewHy abc 9 RSH Quackgrass Cross abcd 10 Douglas Crested Wheatgrass abcd 11 Trailhead Basin Wildrye abcd 12 Broadleaf Crested Wheatgrass abcd 13 Oahe Intermediate Wheatgrass abcde 14 Critana Thickspike Wheatgrass bcde 15 Shoshone Beardless Wheatgrass cdef 16 Altai Wildrye f 17 Spread~r II Alfalfa f 18 Magnar Basin Wildrye f 19 Alfagraze Alfalfa f 20 Remont Sainfoin were quite evident (tables 5 and 6). There was much greater variation in greenness within species by August 10, making it more difficult to distinguish between species statistically. At the sagebrush/grass site on August 10, both varieties of Basin wildrye and Remont sainfoin had ratings of 80 percent green tissue or above. Table 5 shows that the first ten species stayed significantly greener longer than the rest of the species at that site. At the greasewood site, Remont Sainfoin received the highest rating on the last date, with the first 12 species listed on table 6 also being significantly higher than the other species at the site on August 10. By August 10, thirty-eight percent of the plants at the sagebrush/grass site were significantly lower than the rest of the spec;es at that site with Vavilov Siberian wheatgrass receiving the lowest ranking. At the greasewood site, 30 percent of the species were in the statistically lowest ranked group, with Critana thickspike wheatgrass receiving the lowest rank on August 10. Discussion Different plant species have adapted to different types of environmental conditions, with some having a wide range of adaptation, and others having a narrow range. These adaptability trials indicated that the species evaluated represented a wide range of variation with respect to being adapted to these sites. Some species had strong establishment, while others had the ability to remain green into late summer. Some species did well in both areas, while others proved to be mediocre or poor in both categories. Table 5-Percent green tissue remaining for species at the site. Rank Percent green tissue Species July 19 August 10 Magnar Basin Wildrye 89.0 abcd 81.5 a Trailhead Basin Wildrye 85.7 cde 80.0 a Remont Sainfoin 90.0 abc 80.0 a RSH Quackgrass Cross 88.3 abed 75.0 ab Spread~r II Alfalfa 88.0 abcd 73.3 ab NewHy 84.3 def 72.3 abc Goldar Bluebunch Wheatgrass 95.7 a 66.7 abcd SL Hybrid Wheatgrass 94.0 ab 63.3 abcde Secar Snakeriver Wheatgrass 90.0 abc 59.0 abcdef Paloma Indian Ricegrass 64.3 i 55.0 bcdefg Critana Thickspike Wheatgrass 83.7 cde 50.7 cdefgh Regar Meadow Bromegrass 81.3 efg 49.3 defghi Broadleaf Crested Wheatgrass 82.7 ef 48.3 defghi Hycrest II Crested Wheatgrass 87.3 bed 43.3 efghij Hycrest I Crested Wheatgrass 81.7 efg 37.0 fghijk Bannock Thickspike 89.3 abcd 34.0 ghijkl Oahe Intermediate Wheatgrass 83.0 cde 33.3 ghijkl Nordan Crested Wheatgrass 75.3 gh 30.3 hijkl Luna Pubescent Wheatgrass 70.7 hi 28.3 ijkl P27 Siberian Wheatgrass 87.7 abcd 26.7 jkl Ephraim Crested Wheatgrass 78.7 fgh 21.7 jkl Bozoisky Russian Wildrye 81.7 efg 18.7 kl Syn A Russian Wild rye 87.0 bcd 15.7 kl Vavilov Siberian Wheatgrass 82.0 efg 14.0 I 342

5 Table 6-Pereent green tissue remaining for speeies at the site. Percent green tissue Rank Species July 19 August 10 1 Remont Sainfoin 89.0 a 75.0 a 2 Magnar Basin Wildrye 79.7 b 73.3 a 3 Alfagraze Alfalfa 95.0 a 70.0 ab 4 Trailhead Basin Wildrye 79.0 be 70.0 ab 5 NewHy 76.7 bed 67.7 ab 6 RSH Quaekgrass Cross 73.7 bede 67.3 ab 7 Alkar Tall Wheatgrass 79.0 be 67.3 ab 8 Spreador II Alfalfa 79.0 bc 65.0 abe 9 Broadleaf Crested Wheatgrass 71.3 defgh 63.3 abe 10 Altai Wildrye 70.7 bed 60.0 abe 11 Syn A Russian Wildrye 74.0 bede 56.7 abe 12 P27 Siberian Wheatgrass 72.7 edef 55.7 abe 13 Shoshone Beardless Wildrye 77.0 bed 51.7 be 14 Nordan Crested Wheatgrass 67.7 efghi 46.7 ed 15 Hyerest I Crested Wheatgrass 60.7 ijk 28.3 de 16 Vavilov Siberian Wheatgrass 55.3 k 28.3 de 17 Douglas Crested Wheatgrass 58.3jk 26.7 e 18 Bozoisky Russian Wild rye 65.7 fghi 23.3 e 19 Oahe Intermediate Wheatgrass 65.3 ghij 19.0 e 20 Critana Thickspike Wheatgrass 62.3 ijk 11.0 e At the greasewood site, Alkar tall wheatgrass showed good establishment, and also stayed green into August, having 67.3 percent green tissue remaining on August 10. It has been shown to stay green longer than other wheatgrasses (table 6; Asay 1995) which could be attributed to its extremely deep root system (Asay 1995). It was in the statistically highest ranked group for both stand performance and percent green tissue remaining. Tall wheatgrass is one of the foremost species used for revegetation on greasewood sites and is very important for reclamation purposes in these areas (Forsburg 1953; Fleck 1967; Rollins and others 1968; Malcolm 1969; McPhie 1973; Sandoval and Gould 1978; Roundy and others 1983; Roundy 1985). Crested wheatgrass varieties established well on both study sites but did not remain green through the end of the summer. The performance on these sites corresponded with crested wheatgrass performance in other areas. Crested wheatgrass has been found to provide excellent spring forage, but quality declines rapidly (Welsh and others 1993; Asay 1995). Although the crested wheatgrass varieties which were used had low percent green tissue on the last collection date, they still remained green longer than expected from previous reports. This probably occurred because of the especially cool and wet spring and summer in This area received 229 mm of precipitation in May and 68 mm of rain in June, which equaled the long-term mean annual precipjtation. Although crested wheatgrass varieties are not commonly planted for summer forage, its excellent establishment properties make it highly desirable for soil stabilization. For example, the first important use of crested wheatgrass occurred on the Great Plains, saving large tracts of soil during the dust bowl of the 1930's (Asay 1995). Most of the wildrye varieties used in this study have histories of poor seedling vigor and poor establishment properties (Asay 1995). Bozoisky Russian wildrye and Syn A Russian wildrye were both selected for improved establishment and seedling vigor (Asay 1992), and did outperform the other wildryes receiving high scores on the Stand Performance Index (tables 3 and 4). basin wildryes had high percentages of green tissue throughout the summer at both sites (tables 5 and 6). At the sagebrush/grass site neither had strong establishment (tables 3 and 4), while at the greasewood site, Trailhead basin wildrye performed well, receiving an Index score of 75.5 and was in the statistically highest ranked group. Trailhead basin wildrye has been found to outproduce Magnar great basin wildrye under drought conditions (Asay 1995). Basin wildryes have proven to be important plant materials in revegetation of greasewood sites (Roundy and others 1983; Roundy 1985). Thickspike wheatgrass varieties performed average to poor on both sites for stand performance. Critana thickspike, SL hybrid, and Bannock thickspike were not in the highest or lowest groups, but Secar snakeriver wheatgrass was in the statistically lowest group at the sagebrush/grass site. At the sagebrush/grass site, SL hybrid and Secar snakeriver wheatgrass were in the statistically highest group for percent green tissue remaining on August 10. Critana was average, and Bannock thickspike was in the statistically lowest grou p. Secar snakeriver w heatgrass has shown excellent drought tolerance in the past (Asay 1995). SL hybrid also has drought tolerance (Asay and others 1991). Bluebunch wheatgrass performed very poorly at the sagebrush/grass site, being in the statistically lowest group for stand performance. On the greasewood site NewHy and RSH quackgrass cross were in the statistically highest group. It is not surprising that these two varieties would act similarly because they are both crosses between bluebunch wheatgrass and quackgrass (Asay 1992). RSH is the naturally occurring form ofn ew Hy. It is also not surprising that they would do well on the greasewood site because they have high salt tolerance. Bluebunch wheatgrass was in the statistically highest group at both sites for percent green tissue remaining on August 10. This supports other findings that bluebunch wheatgrass is adapted to dry areas (Asay 1995). Although Regar meadow bromegrass has shown rapid seedling establishment in other areas (USDA 1994), it was in the statistically lowest group for stand performance, receiving an index score of 6.2 at the sagebrush/grass site (table 3). It has also shown drought tolerance in other areas (USDA 1994), but received a marginal rating of percent green tissue remaining (table 5). Paloma Indian rice grass performed marginally in stand performance and percent green tissue remaining (tables 3 and 5). In other areas it has shown excellent stand establishment and relative drought tolerance (USDA 1994). Although both varieties of alfalfa, Spreador II and Alfagraze, did not receive high Stand Performance Index scores, alfalfa would be a valuable plant to have in a species mix. Mature alfalfa plants can recover from heavy grazing, while seedlings have great difficulty recovering (Stevens and Monsen 1998). Alfagraze alfalfa is adapted to areas that are irrigated or have average annual precipitation higher than at these sites (Monsen and Horrocks 1996, personal communication), as such, it is not surprising that it did not exhibit high performance under extreme conditions. 343

6 Alfagraze probably should not be used in seeding mixes in these environments without irrigation. IfSpreador II seedlings can be protected for 2 or 3 years, surviving plants should be long lived in the community (Stevens and Monsen 1998). The value of including a legume like alfalfa in a mix is that it greens up early and stays green longer than many grasses (Stevens and Monsen 1998). Remont sainfoin is another plant which demonstrated poor establishment, but ifit could be established, it would be valuable for grazing purposes. It greens up early and stays green long into the grazing season (Stevens and Monsen 1998). Remont Sainfoin remained green longer than almost all of the species at both sites (tables 5 and 6). The high establishment and growth rate for many species on the greasewood site was unusual for such a site. Success could be attributed to high amounts of precipitation in the spring of 1995 (Roundy and others 1983; Roundy 1985). Another possible explanation, is that the site is sodic and not saline-sodic. Available water would not have been restricted by low matric and osmotic potentials as is often the case in saline soils (Rollins and others 1968; Sandoval and Gould 1978; Roundy and others 1983; Roundy 1985). Conclusions Reclamation projects can have many different objectives. The desired objectives of the project determines what plant species are used. If the objective is soil stabilization then crested wheatgrass would be a good species to use. If the objectives included lengthening the grazing season, then a species like alfalfa, which remains green through the summer, would be a better choice. Plant species used also depends on the site being reclaimed. For example, Trailhead basin wildrye had an Index score of 47.6 at the sagebrush! grass site while receiving a score of75.5 on the greasewood site. Difference in soil type, water relations, and history of use can impact the site and which species are adapted. Although objectives for an area will help determine which species should be planted, a mix of native and introduced grasses along with some shrubs has been shown to improve overall plant prod uction in arid and semi arid areas (Roundy and Call 1988). Further studies could be performed to determine which mix of species grow best together, and to determine which species are preferred by grazing animals. References Allen, E. B Restoration ecology: limits and possibilities in arid and semiarid lands. p IN: Roundy, B. A; McArthur, E. D.; Haley, J. S.; Mann, D. K. (eds.) Proceedings: Wildland Shrub and Arid Land Restoration Symposium. INT-GTR-315 Intermountain Research Station Forest Service USDA, Ogden. Asay, K. H Breeding potentials in perennial Triticeae grasses. Hereditas. 116: Asay, K. H The wheatgrasses and wildryes: The perennial Triticeae. p IN: Barnes, R B.; Miller, D. 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